防灾减灾系统灾情信息集成技术研究

全球各类自然灾害的频繁发生,给各国人民的生活和生产带来了严重灾难和重大损失。通过建立防灾减灾系统,有效减少灾害带来的损失,越来越受到各国政府及灾害主管部门的重视。本文结合地理信息系统的地理编码技术、大型关系数据库技术、动态数据交换技术,详细阐述了应用于政府部门的防灾减灾系统中灾情信息的集成方法及具体实现。     

Spatial patterns of groundwater‐lake exchange – implications for acid neutralization processes in an acid mine lake

Exchange of groundwater and lake water with typically quite different chemical composition is an important driver for biogeochemical processes at the groundwater‐lake interface, which can affect the water quality of lakes. This is of particular relevance in mine lakes where anoxic and slightly acidic groundwater mixes with oxic and acidic lake water (pH < 3). To identify links between groundwater‐lake exchange rates and acid neutralization processes in the sediments, exchange rates were quantified and related to pore‐water pH, sulfate and iron concentrations as well as sulfate reduction rates within the sediment. Seepage rates measured with seepage meters (?2.5 to 5.8 L m^‐2 d^‐1) were in reasonable agreement with rates inverted from modeled chloride profiles (?1.8 to 8.1 L m^‐2 d^‐1). Large‐scale exchange patterns were defined by the (hydro)geologic setting but superimposed by smaller scale variations caused by variability in sediment texture. Sites characterized by groundwater upwelling (flow into the lake) and sites where flow alternated between upwelling and downwelling were identified. Observed chloride profiles at the alternating sites reflected the transient flow regime. Seepage direction, as well as seepage rate, were found to influence pH, sulfate and iron profiles and the associated sulfate reduction rates. Under alternating conditions proton‐consuming processes, for example, sulfate reduction, were slowed. In the uppermost layer of the sediment (max. 5 cm), sulfate reduction rates were significantly higher at upwelling (>330 nmol g^‐1 d^‐1) compared to alternating sites (<220 nmol g^‐1 d^‐1). Although differences in sulfate reduction rates could not be explained solely by different flux rates, they were clearly related to the prevailing groundwater‐lake exchange patterns and the associated pH conditions. Our findings strongly suggest that groundwater‐lake exchange has significant effects on the biogeochemical processes that are coupled to sulfate reduction such as acidity retention and precipitation of iron sulfides. Copyright © 2012 John Wiley & Sons, Ltd.     

Falling sphere observations of anisotropic gravity wave motions in the upper stratosphere over Australia

A study of inertial scale gravity wave motions in the region of the atmosphere between 30 and 60 km has been undertaken, using wind and temperature data derived from rocket-borne falling sphere density experiments performed over Woomera, Australia between 1962 nad 1976. The gross features of the wave field compare favorably with those found in similar northern hemispheric studies. Wave propagation is found to be both vertically and horizontally anisotropic. A rotary spectral analysis indicates predominately upgoing wave energy, suggesting that the majority of sources of these waves lie below 30 km. A detailed statistical investigation of the waves, made using the Stokes parameters technique, reveals that phase progression is also highly directional in the horizontal, with a significant zonal component in summer, but with a strong meridional component in winter. Propagation towards the southeast is inferred in summer, with the waves possibly emanating from tropospheric sources in equatorial regions to the north of Australia. The technique also shows that, on average, the waves appear to have mean ellipse eccentricities (=f/) around 0.4–0.45. Indirect estimates of a number of important wave parameters are made. In particular,v andw flux estimates are made over several height intervals. The vertical gradient of density weighted flux implies wave-induced mean flow accelerations of the order 0.1–1 ms^–1day^–1. This suggests that dissipating gravity waves are a significant source of the momentum residuals that are encountered in studies of satellite data from this region.     

Annual heat balance and equilibrium temperature of Lake Aegeri,Switzerland

The mean heat budget of Lake Aegeri, Switzerland, is 950 MJ·m^–2, comparable to that of neighbouring lakes. The annual variation in the net heat flux can be adequately described using a six-term heat balance equation based on 12 years of monthly mean meteorological and surface temperature data. Although the magnitude of the net heat flux is dominated by the radiative terms of the equation, the one-month backward shift of the net flux and total heat content extrema from the solstices and equinoxes respectively is due to the phase shift of the non-radiative with respect to the radiative terms. A linear approximation was used to express the net heat flux in terms of a heat exchange coefficient and an equilibrium temperature. The former varies from 17 to 28 W·m^–2·K^–1 in the course of a year; fluctuations in the latter are found to depend mainly on fluctuations in cloud cover and relative humidity, whilst the effect of fluctuations in air temperature and wind speed is slight.     

空间运输联系的分布与交流规律研究

空间运输联系是指在自然、社会、经济诸要素综合作用下，区域间通过交通运输设施进行旅客和货物交流产生的相互联系与作用。采用定量与定性相结合的实证分析方法，本文研究了客货运输的地域分布特征、地域间交流联系生成的内在机制、基本类型和增长演变的趋势，划分出客运联系“单中心”、“多中心”，货运联系“互补性交流”、“竞争性交流”、“递接性交流等类型，并提出了非均衡系数、集中度、首位联系量等评价指标。     

The biogeochemical sulfur cycle in the marine boundary layer over the Northeast Pacific Ocean

The major components of the marine boundary layer biogeochemical sulfur cycle were measured simultaneously onshore and off the coast of Washington State, U.S.A. during May 1987. Seawater dimethylsulfide (DMS) concentrations on the continental shelf were strongly influenced by coastal upwelling. Concentration further offshore were typical of summer values (2.2 nmol/L) at this latitude. Although seawater DMS concentrations were high on the biologically productive continental shelf (2–12 nmol/L), this region had no measurable effect on atmospheric DMS concentrations. Atmospheric DMS concentrations (0.1–12 nmol/m³), however, were extremely dependent upon wind speed and boundary layer height. Although there appeared to be an appreciable input of non-sea-salt sulfate to the marine boundary layer from the free troposphere, the local flux of DMS from the ocean to the atmosphere was sufficient to balance the remainder of the sulfur budget.     

On the general character of coastal flow

It is well-known that some coastal currents such as the Florida Current have a recirculating region on their coastal side, while other currents such as the East Australian Current have no such region. Under the hypothesis that the form drag on a coastal current by an irregular coastal topography reduces the momentum transport of the current to a minimum for the given flow within the current, the hydraulic theory of coastal currents is used to explain this behaviour.     

离子交换与吸附研究方法

综合文献资料，结合本人研究实践，对离子交换与吸附研究的一些方法做专门介绍．     

Effect of relative humidity on the angular distribution of scattered light intensity for rural and urban aerosols

The change in atmospheric relative humidity affects the physical and optical properties of aerosol particles. It would be interesting to study the effect of an increase in relative humidity on the angular scattering of light by aerosols (by incorporating the changes due to it as the complex refractive index and the parameters of the size distribution function). In the present paper we have computed the angular scattering function for rural and urban aerosols, for light of wavelength 0.55 μn. The results obtained for these two models, representative of different environments, are interesting and show some discriminating features.     

Trace gas measurements during aircraft flights in the tropopause region over Europe and North Africa

During aircraft flights in May 1981 from Munich (40°N) to north of the Spitsbergen Islands (82°N) and to Monrovia, Liberia (6°N), air samples were obtained in the altitude range of 8 to 11 km and during the ascents and descents near the airports. These samples have been analyzed for the trace gas mixing ratios of CH₄, CO and N₂O. The results of these analyses are presented and discussed.The results provide new evidence of tropospheric-stratospheric exchange events in the vicinity of the subpolar and subtropical tropopause foldings and possibly show a case of transport of CO-enriched air in the upper troposphere above the North Atlantic Ocean.